class_docstr: Tests for moment matrix
docstr: Test that moment_matrix returns the correct matrix when no differentiable parameter is
  used.
docstr_tok: ["Test","that","moment_matrix","returns","the","correct","matrix","when","no","differentiable","parameter","is","used","."]
code: def test_moment_matrix_nodiff(self, symbols, geometry, e, idx, s_ref):
      r"""Test that moment_matrix returns the correct matrix when no differentiable parameter is
      used."""
      mol = qchem.Molecule(symbols, geometry)
      s = qchem.moment_matrix(mol.basis_set, e, idx)()
      assert np.allclose(s, s_ref)
  
imports: import pytest
  import pennylane
  from pennylane import numpy
  from pennylane import qchem
label_desc: Use image node_id 2 for calling the TestMomentMat obj's underlying member method code with example usage: obj.test_moment_matrix_nodiff(symbols, geometry, e, idx, s_ref) without return types